This invention relates generally to a refrigeration apparatus, and more specifically pertains to a dual compartment with independent temperature maintenance through the cooperation of select thermostatic controls and valve means.
Innumerable styles of refrigerated display cases are available in the prior art. For example, such cases usually incorporate an insulated housing containing a variety of shelves and having either access means in the form of doors, such as pivotal or sliding doors, enclosing the compartment, or even being of the open display case type wherein the reach-in portion of the case remains permanently opened, relying upon the heavier specific gravity of chilled air to remain cradled within the lower reaches of the compartment so as to prevent its escape through heat dissipation.
Usually, though, such display cases incorporate a variety of refrigeration means, as for example, independent refrigeration means for each portion or compartment of the case where varying temperatures may be desired, if multi temperatures are included. For example, in the U.S. Pat. to Knapp, No. 1,979,625, there is disclosed a dual temperature display case which is used for preserving supplies in a frozen condition, and at the same time, maintain the storage and display of foods at normal refrigerated temperatures. And, to achieve such, a variety of refrigerant evaporators are rendered functional from either a single or separate compressor-condenser structures, without the use of independent control, so therefore, when a temperature within one compartment as mentioned may exceed the desirable limit, the refrigerating apparatus is initiated so as to lower that temperature to that desired, without regard for the fact that the temperature within the other section may already be located at its preferred level. To remedy this problem, the U.S. Pat. to Sanders, No. 3,010,291, discloses a refrigerating apparatus wherein its above-freezing and sub-freezing compartments are independently cooled by separate refrigerating means, which may provide the preferred control for the separate temperature maintenance, but because of the necessity for utilizing independent refrigerating means to do so, the cost of such a unit is greatly enhanced through this redundancy.
Various other styles of refrigerated display cases incorporate the use of a plurality of evaporators, for maintaining temperatures within various sections of the case, but usually, such evaporators are generally rendered functional by an independent refrigerating means, without independent control of the flow of the refrigerant simultaneously to all of its accompanying evaporators. This is shown in the U.S. Pat. to Burtis, No. 2,490,413. Other refrigerating display cases of this type are shown in the U.S. Pat. to Banta, Nos. 1,981,298, Spangler, No. 2,495,554 and Warren, No. 2,501,459.
In view of the foregoing, it is the principal object of this invention to provide a dual temperature merchandiser having independent refrigerant flow to discrete evaporators located within separate but communicating compartments of the merchandiser, wherein temperatures may be precisely regulated through independent thermostatic and valve controls.
Another object of this invention is to provide a dual temperature merchandiser wherein the chilling temperatures approximating 35.degree. F. may be precisely regulated within its upper compartment while the overflow from said compartment will blanket and assist in sustaining a freezing temperature within the vicinity of a -10.degree. F. within the lower compartment, while the same refrigerating apparatus may selectively operate to decrease the subzero temperature within this lower compartment and hold it at its desired lower level.
A further object of this invention is to provide a dual temp merchandiser wherein its subfreezing lower temperature is selectively and efficiently maintained due to the location of evaporator coils conveniently surrounding the walls of the said compartment.
Another object of this invention is to provide a means for properly controlling the temperature interface between a refrigerating compartment and a subfreezing compartment maintained therebelow through the usage of conveniently located frost breakers.
A further object of this invention is to provide the construction of a dual temperature merchandiser wherein a significantly sized access aperture into the compartment is conveniently arranged adjacent the refrigerating compartment, but yet furnishes convenient access within the standard reach into a lower disposed subfreezing compartment wherein frozen foods or other products may be stored and displayed.
Yet another object of this invention is the provision of a variety of shelving for use within a dual temperature merchandiser and which are readily replaceable, adding to the convenience and prompt display of refrigerated products at the market.
Still another object of this invention is to provide means for illuminating a dual temperature merchandiser wherein conveniently disposed lighting not only brightens its display area, but also can be used for lighting a display for advertising the selection of the merchandiser.
Still another object of this invention is to provide convenience in the disposition of the compressor and condenser of the refrigerating means, making it readily accessible through its mounting upon a removable tray that can be conveniently slid forwardly of the merchandiser and readily serviced by the mechanic.
These and other objects will become more apparent to those skilled in the art upon reviewing the summary of this invention, and upon undertaking a study of the description of its preferred embodiment in view of the accompanying drawings.